Felice jacoviello



F. JACOVIELLO.

I ELECTRIC FURNACE. APPLICATION FILED JAN.3, 1919.

Patented Dec. 9, 1919.

FELICE JACOVIELLO, 0F MILANO, ITALY.

ELECTRIC FURNACE.

Specificatm of Letters Patent.

Patented Dec. 9, 1919.

Application filed January 3, 1919. Serial No. 269,545.

To all whom it may concern:

Be it known that I, FELicn JACOVIELLO, a subject of the King of Italy, residing. at Milano, Kingdom of Italy, have invented certain new and useful Improvements in Electric Furnaces, of which the following is a specification.

The present invention relates to complex electrical resistances for electric furnaces; and it resides in the provision of an improved resistance for the purpose stated composed of alternately-arranged layers of substances of high and low electrical conductivity. The invention is characterized by the fact that 'the layers of high conductivity are in the fornrof hollow bodies which provide internal recesses to. enable various physical and chemical phenomena to take place therein at high temperatures, viz: fusion and distillation, reduction of oxids, fixation of nitrogen, formation of carbids, and breaking down of compounds obtained at low temperatures and attendant distillation of some of the substances thus separated or disengaged. For example, at a temperature of 1890 (1., it is possible to obtain carbids of calcium, silicon and aluminum, while at very high temperatures the said carbids can be broken down, and at the same time distillation of the calcium, silicon and aluminum will take place with a deposit of graphite.

The accompanying drawing shows vertical sectional views of two forms of electric furnaces provided with electric resistances according to the invention.

In the construction represented in Figure 1, R indicates the walls or shell of a furnace, which may be rotated by suitable mechanism (not shown), and which contains a plurality of graphite crucibles C embedded in powdered coal or graphite P which connects them in series. In operating this furnace use is made of a pipe or conduit which communicates with the upper portion of each crucible and which is located exteriorly of the furnace, so that during the rotation of the furance the molten metal. can be poured from all of the crucibles.

The furnace illustrated in Fig. 2 is designed for the distillation of zinc, and comprises a plurality of mufflcs M which are likewise embedded in powdered coal or graphite P and connected in series thereby, the walls of the furnace being indicated at R. The electrodes are indicated at E in both figures, and have portions thereof embedded in the low conductive material P at opposite ends of the furnace. The inn-flies M are constructed of briquets of coal dust or graphite bonded together by means of tar or pitch, and they may, if desired, have the same size and shape as those employed in the so-called Silesian system.

In both of the arrangements above described, it is to be observed that the aforementioned physical and chemical phenomena are produced in the interiors of the hollow bodies 0 and M of high conductivity by reason of the high tempertures which are set up in the masses of powdered material P interposed between them. That is to say, the powdered material, being of much lower conductivity than the hollow bodies, will offer correspondingly greater resistance to the current, which will pass from one to another of said bodies without developing any sensible amount of heat therein.

I claim as my invention 1. In an electric furnace, a plurality of electrically-conductive, hollow bodies disposed within the furnace in spaced relation to contain the substances undergoing treatment, and masses of powdered electricallyconductive material within the furnace interposed in the spaces between said bodies and incasing the same so as to connect them in series; in combination with a pair of electrodes having portions thereof embedded in the powdered material at opposite ends of the furnace, the conductivity of the powdered material being relatively low, and that of the hollow bodies being relatively high, whereby the current, in passing from one electrode to the other, will be caused to successively traverse the alternating masses of powdered material and hollow bodies, setting up high heat in the former but meet- -ing with low resistanpe in the latter so as to avoid generating high heat therein during its passage therethrough; substantially as described. 7

2. In an electric furnace, a plurality of electrically-conductive, hollow bodies disposed within the furnace in spaced relation to contain the substances undergoing treatment, and layers of electrically-conductive material incasing said bodies and connecting them in series; in combination with a pair of electrodes connected to the layers of low conductivity at opposite ends of the furnace, the conductivity of said layers being relatively low and that of said hollow bodies being relatively high, whereby the current, in passing from one electrode to the other, will be caused to successively traverse the alternating layers and hollow bodies, setting up high heat in the former but meeting with low. resistance in the latter, so as to avoid generating hi h heat therein during its passage therethrough; substantially as described.

3. In an electric furnace, a plurality of 'electrically-conductive, hollow bodies disposed within the furnace in spaced relation to contain the substances undergoing treatment and having their walls formed or briquets of pulverized carbonaceous material bonded together with tarry material, and

masses of powdered, electrically-conductive material within the furnace interposed in the spaces between said 'bodies and incas- 20 ing the same so as to connect them in series;

in combination with apair of electrodes having portions thereof embedded in the powdered material at opposite ends of the furnace, the conductivity of the owdered material being relatively low, an that of the hollow bodies being relatively high, whereb the current, in passing from one electro e to the other, will be caused to suecessively traverse the alternatin masses of powdered material and hollow %)odies, setting up high heat in the former but meeting with low resistance in the latter so as to avoid generating high heat therein during its passage therethrough; substantially as 35 described.

In testimony whereof I aflix my signature.

FELICE JACOVIELLO. 

